Lucent to Pitch MSOs On Over-Air Optics

12/12/1999 7:00 PM Eastern

By: FRED DAWSON

Cable operators will be introduced to a new over-the-airmultiple-wavelength optical system from Lucent Technologies this week that could easeindustry expansion into high-definition television and business services.

Lucent has been working on an iteration of its new"OpticAir" system specifically for use in cable, officials said. They declinedto go into detail, but it appeared that the application would be aimed at providingtransport support for bandwidth-consuming HDTV signals.

Possibly more significant, the new technology has majorpotential for anyone seeking to deliver high-bandwidth services to the business sector,insofar as it offers a low-cost optical connection from a fiber-ring network, for example,to large buildings.

Because the system operates within the establishedwavelength standards set for transmissions in the 1550-nanometer "window," itoffers a means of connecting end-users over dedicated wavelengths seamlessly across thefiber and free-space transmission hops, officials said.

"The OpticAir system operates at 1550 nm, unliketraditional over-the-air optical systems, which allows us to transmit in multiplewavelengths and to use EDFAs," or erbium-doped fiber amplifiers, said Frank Galuppo,director for OpticAir products in Lucent's optical-networking group.

For TV applications, Lucent is already talking withtelevision broadcasters about using the technology to backhaul studio-quality HDTVsignals, Galuppo said. "Broadcasters could set up our system at a live sports eventand transmit back to their studios, avoiding the need to set up high-capacity fiberlinks," he added.

The system could also be used by broadcasters to distributetheir signals to cable headends, Galuppo noted. These types of applications requiretransmissions in uncompressed format to ensure extremely high quality, and they cannoteasily be accommodated with traditional fiber feeds, Galuppo noted.

The OpticAir system is designed to meet thehigh-performance requirements of traditional telecommunications markets, with reliabilityat "four or five nines," or 99.99 to 99.999 percent, Galuppo said. Depending onatmospheric conditions, this could mean distances limited to as little as 400 meters or asfar as 5 kilometers, although early versions of the system, to be deployed commerciallythis spring, will be limited to 2 kilometers as a precautionary measure, he added.

"Fog is the worst problem by far, with snow and rain adistant second," Galuppo said. Setting a 400-meter distance as the worst-caseparameter, the company believes atmosphere would not be a problem in most areas, even withpersistent fog patterns, he added.

The first OpticAir product will deliver one wavelength at2.5 gigabits per second, with an eight-wavelength version due for production starting inSeptember. "We recently demonstrated 16 wavelengths, but we haven't set a timeframe for moving to that level," Galuppo said.

"I think it's safe to say that we have never hadmarket reception for a transmission product like we've seen for OpticAir," headded. "The response has been more than overwhelming."

The product not only eliminates the cost of installingfiber, but the actual transmission and receiving gear is slightly less expensive than suchgear would be for making the connection over fiber, Galuppo said.

This has important implications for the ability to getreliable high-speed connections to large buildings, only 5 percent of which are connectedvia fiber nationally, he said.

Another major application category for the technology isthe rapidly growing fixed-wireless industry, which needs some means of interconnectingtransmitter hubs.

Sprint Corp. is looking seriously at over-the-air optics asan option for interconnecting the multiple MMDS (multichannel multipoint distributionservice) hubs it plans to install as it expands into two-way communications over thewireless infrastructure, said Frank DeNap, director of the Advanced Technology Labs atSprint.

"It's one of the options we're consideringfor our backhaul requirements, along with LMDS [local multipoint distribution service] andfiber," DeNap said. "We could end up using all three, depending on local marketconditions."

For Sprint, the LMDS option would likely involve the use ofspectrum held by another provider, since it does not hold any LMDS spectrum. Meanwhile,LMDS providers are likely users of the OpticAir system as they seek to maximize use oftheir spectrum for reaching end-users while turning to other means to link theirtransmitters.

"There's definitely a need to reserve ourspectrum if we can find a cheap alternative for backhaul," said a senior executive atone of the leading LMDS license-holders, asking not to be named. "We're taking ahard look at OpticAir, but it's too early to say whether it will meet our performancerequirements."

The OpticAir system uses what Galuppo called"telescope" transmitters, four of which generate "expanded-beam"signals to the targeted user premises in a way that minimizes dispersion of the lightthrough the air. The system meets the class-1 requirements of the safety standard foroptical transmissions, which means a person could look right into the transmitter withbinoculars and not be affected, he said.

The first publicly announced user of the OpticAir system islong-haul carrier Global Crossing Ltd., which is launching field trials this month.